• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.248.1-248
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• 1997

No Abstract, See Full Text

• Polymer Science and Technology
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• v.24 no.3
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• pp.285-293
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• 2013

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.04a
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• pp.137-146
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• 2000

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2017.10a
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• pp.245-246
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• 2017

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.66-75
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• 2015

Disposable diaper waste is consisted of plastic, fiber, and SAP (Super Absorbent Polymer). They are valuable to be used as raw materials of other products including plastic blocks and pulp mold. Nevertheless, disposable diaper waste have been disposed by landfill and incineration without recycling. Due to strict environmental regulations it is necessary to develop fractionation technique to recycle the disposable diaper waste. In this study the fractionation technique using pilot-scale stock preparation units was investigated. Process for separation of plastic and fibers from disposable diaper waste was composed by the combination of pilot-scale pulper, drum screen, screen and cleaner. Recovery rate of plastics and fiber was checked according to the various operating conditions. In drum screen, recovery rate of plastic was high when the cut size of disposable diaper waste was $5cm{\times}5cm$. The highest recovery rate of fiber was achieved with 0.3 mm slot screen. It is important to control the neutral state of SAP for improvement of recovery rate of fiber since SAP can be swelled easily in water. Therefore SAP can be controlled efficiently by the addition of calcium chloride into the pulper. Consequently recovery rates of plastics and fibers were over 90 and 80% under the optimum pilot operating conditions.

• Journal of Soil and Groundwater Environment
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• v.22 no.1
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• pp.18-26
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• 2017

In a previous study, we assessed the feasibility of ferric chloride ($FeCl_3$) as a washing agent in bench-scale in-situ soil washing to remove Pb from agricultural paddy soil. Herein is a subsequent study to evaluate variations in soil properties after $FeCl_3$ soil washing in terms of fractionation and bioavailability of Pb and chemical properties of the soil. After soil washing, the soil pH decreased from 4.8 to 2.6 and the exchangeable fractions of Pb in the soil increased from 12 mg/kg to 15 mg/kg. Variations in the Pb fractionation of the soil increased Pb bioavailability by almost three-fold; however,the base saturation decreased by 75%. The concentrations of total nitrogen and available phosphate were similar before and after soil washing. The available silicate concentration significantly increased after soil washing but was two times lower than that of soil washed with HCl, which is widely used as a washing agent. This indicates that $FeCl_3$ can be an acceptable washing agent that protects the soil clay structure. The results suggest that soil amendment, such as liming, is needed to recover soil pH, reduce mobility of Pb, and provide exchangeable bases of Ca, Mg, and K as essential elements for the healthy growth of rice plants in reused soil that has been washed.

• Biomolecules & Therapeutics
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• v.24 no.4
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• pp.438-445
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• 2016

Cyperi Rhizoma (CR), the rhizome of Cyperus rotundus L., exhibits neuroprotective effects in in vitro and in vivo models of neuronal diseases. Nevertheless, no study has aimed at finding the neuroactive constituent(s) of CR. In this study, we identified active compounds in a CR extract (CRE) using bioactivity-guided fractionation. We first compared the anti-oxidative and neuroprotective activities of four fractions and the CRE total extract. Only the ethyl acetate (EA) fraction revealed strong activity, and further isolation from the bioactive EA fraction yielded nine constituents: scirpusin A (1), scirpusin B (2), luteolin (3), 6'-acetyl-3,6-diferuloylsucrose (4), 4',6' diacetyl-3,6-diferuloylsucrose (5), p-coumaric acid (6), ferulic acid (7), pinellic acid (8), and fulgidic acid (9). The activities of constituents 1-9 were assessed in terms of anti-oxidative, neuroprotective, anti-inflammatory, and anti-amyloid-${\beta}$ activities. Constituents 1, 2, and 3 exhibited strong activities; constituents 1 and 2 were characterized for the first time in this study. These results provide evidence for the value of CRE as a source of multi-functional neuroprotectants, and constituents 1 and 2 may represent new candidates for further development in therapeutic use against neurodegenerative diseases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.2
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• pp.193-197
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• 1997

Elevation of the activities of phase 2 enzymes such as quinone reductase(QR) provides protection against several types of neoplasia. In this study, we performed partial purification of QR inducer(s) from roasted and defatted perilla meal by solvent fractionation and thin layer chromatography. Cellular QR induction was most notable in chloroform fraction of roasted perilla extract, compared with other solvent fractions. QR inducer(s) was partially purified by TLC, with 0.8 of $R_f$ value in n-butanol : n-propanol : 2N-ammonium hydroxide(10 : 60 : 30). AHH-inducing activity in TLC fractions isolated from methanol extracts of roasted perilla comigrated with QR-inducing fraction, suggesting that QR and AHH are induced by the same compound. TLC fractions shown strong QR-inducing activity also had a potent antioxidative activity, suggesting that cellular QR enzyme is induced by antioxidant(s) present in roasted perilla.

• Analytical Science and Technology
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• v.6 no.5
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• pp.453-462
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• 1993

The retention behaviors of polystyrenes influenced by mixed solvents are examined in thermal field-flow fractionation(ThFFF). Experimental data are obtained with polystyrene samples of molecular weights of 35,000, 110,000, 200,000 and 470,000 dissolved in organic solvents. The pure and mixed solvents are tetrahydrofuran(THF), chloroform(CHL), cyclohexane(CH), and benzene(BZ), respectively. The values of retention ratio(R) and thermal diffusion coefficient($D_T$) are measured with change of molecular weight and composition of mixed solvents. Atempts are then made to correlate the measured values with various physicochemical parameters of polymers and solvents. Studies suggest that R is significantly increased with the density of solvent and a good correlation is found between them. $D_T$ values decreases in the mixed solvent having has a higher concentration of poor solvent.

• Analytical Science and Technology
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• v.24 no.4
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• pp.249-255
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• 2011

Swelling of starch granules by water-sorption causes a progressive or sometimes abrupt change in sorption behavior as a result of structural alterations and the possible exposure of new sites with high affinity for water. It is thus of interest to examine the time-dependent change in the size or shape of the starch granules. Gravitational field-flow fractionation (GrFFF) utilizes the earth's gravity as the external field, and is useful for separation of micron-sized particles with larger particles eluting earlier than smaller ones. In this study, GrFFF was used to monitor the swelling of two starch granules, potato starch and sweet potato starch during contact time of 11-12 days at room temperature in water. Results from GrFFF were compared with those obtained from optical microscope (OM). For both starch granules, the mean sizes were increased with time spent in water.